I've received and used a cereal box before. I received some in an orange juice box once. You know like you'd get at Cosco-the box that held 2 cartons of OJ. Not a cleaned out oj container. If you don't have a box around-you could wrap them up in celphane as one unit then wrap with thick paper and tape well to protect. I did this once as well when I didn't have a box that worked.

If they are all the same size, you can make dense "bricks" with lots of plastic wrap and secure taping and then wrap as a birthday present with paper and lots of tape. Also, you can reinforce one or more sides with cardboard (get a big box and cut off the pieces you need.)